Question

why do most leaves have a flat and both surface?

Answer 1

Heya !

Leaves have flat and broad surface so that they can be more exposed towards sunlight which results in more photosynthesis.

Hope this helps !

Answer 2

its main function are photosynthesis and gas exchange. a leaf is often flat, so it absorbs the most light ,and thin so the sunlight can get to the chloroplasts in the cells . most leaves have stomata , which opens and close . they regulate carbon dioxide , oxygen and water vapour exchange with the atmosphere